CVE-2026-27734CWE-22

Beszel Vulnerable to Docker API Path Traversal via Unsanitized Container ID

Medium · published February 27, 2026

CVSS v3.1
6.5
EPSS
1%
Percentile
43.1
In the wild
Unconfirmed
What it is

Beszel is a server monitoring platform. Prior to version 0.18.2, the hub's authenticated API endpoints GET /api/beszel/containers/logs and GET /api/beszel/containers/info pass the user-supplied "container" query parameter to the agent without validation. The agent constructs Docker Engine API URLs using fmt.Sprintf with the raw value instead of url.PathEscape(). Since Go's http.Client does not sanitize `../` sequences from URL paths sent over unix sockets, an authenticated user (including readonly role) can traverse to arbitrary Docker API endpoints on agent hosts, exposing sensitive infrastructure details. Version 0.18.4 fixes the issue.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00516 · 43.1th percentile
Weakness
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Published
2026-02-27T19:41Z
EPSS history
Timeline
  • 27 FEB 19:41Z
    Beszel Vulnerable to Docker API Path Traversal via Unsanitized Container ID
    cvelistv5